Generative Design Investment Casted Stainless Steel 58mm Espresso Portafilter

I designed and cast a generative design inspired (also by H.R. Giger) 58 mm bottomless portafilter that fuses the shaping freedom of 3-D printing with the traditional technique of stainless-steel investment casting. Traditional portafilters haven’t changed in decades, yet baristas still wrestle with ergonomic strain, poor thermal mass, and generic aesthetics. By printing the pattern in a special PLA material, then go through lost-wax casting it in 304 stainless, I could free myself from design limit, creating this impossible portafilter. The result is a 400-500gram portafilter, with shocking look. I built it to prove that boutique metal art can also be functional hardware, and to give home baristas a piece that feels engineered, not just accessorized.

Design

1. CAD software - autodesk fusion (Topology concept)
2. CAD software - Rhino + grasshopper (parametric design)

Pattern-making

1. FDM 3d printer - Bambulab X1C
2. Filament - preferrably polymaker polycast

Shell-building

1. We are working with our own casting foundry so what we have is industrialized equipment, not referrable, you may find very detailed tutorials of household trial of casting shell, so I left this step blank.

Tunnel Furnace

1. Burning PLA off

More detailed steps after Pouring please refer to our site

Our design started with topology optimization as portafilters work under certain condition, topology optimization would provide very good undersatanding of agressive design language. From here to use Rhino to shape our design and fine tune it with our design language.

1. 3D printing is simple, make sure the support is activated.
2. Added 2 % isotropic shrink allowance (304L loses ~1.8 %)

1. 6 layers of zicon sand with silica sol gel processed in dry and controlled temperature
2. Baked in tunnal furnace to remove the PLA plastic, this is the lost PLA process, leaving the cavity empty and prepare the shell for pouring.
3. After pouring, parts cooled down in air and we break the shell.

After possessing the rough parts, we start cutting and grinding, untill the parts become shiny.